1. Field of the Invention
The present invention relates generally to a seal for a vacuum system, and more particularly, a seal for sealing and load bearing a process tube in a chamber.
2. Discussion of the Background
FIG. 1 depicts a plasma chamber arrangement that includes a process tube 210 having a mounting rim 212 that is mounted within a metal housing or processing chamber by clamping the mounting rim 212 between a first metal housing section 214 and a second metal housing section 216. The process tube 210 defines a vacuum chamber 200 on one side thereof and a coolant fluid chamber 202 on a second side thereof. The coolant fluid within the coolant fluid chamber 202 is used to control the temperature of the process tube 210. Such a configuration requires a gas seal 220 on one side of the mounting rim 212, and a coolant fluid seal 230 on a second side of the mounting rim 212. Additionally, it may be necessary to provide a load bearing spacer 240 between the first metal housing section 214 and the mounting rim 212, and a load bearing spacer 250 between the second metal housing section 216 and the mounting rim 212 in order to prevent high stress point loading of the mounting rim 212, which could result in cracking and failure of the process tube 210.
The configuration depicted in FIG. 1 requires that two precision cuts be made in each of the metal housing sections, one for each load bearing spacer and one for each seal. Therefore, a total of four precision cuts need to be made in order to construct the configuration depicted in FIG. 1. Such precision cuts are difficult and expensive to make, and occupy a large amount of area on the metal housing. Accordingly, there is a need for an improved seal configuration.
FIG. 3 depicts a plasma chamber arrangement that includes a process tube 310 having a mounting rim 312 that is mounted within a metal housing or processing chamber by affixing the mounting rim 312 to a metal housing section 314. The process tube 310 defines a vacuum chamber 300 on one side thereof and a coolant fluid chamber 302 on a second side thereof. Such a configuration requires a gas seal 320, and a coolant fluid seal 330. Additionally, it may be necessary to provide a load bearing spacer 340 between the metal housing section 314 and the mounting rim 312 in order to prevent high stress point loading of the mounting rim 312, which could result in cracking and failure of the process tube 310.
The configuration depicted in FIG. 3 requires that three precision cuts be made in the metal housing section, one for the load bearing spacer and one for each seal. Such precision cuts are difficult and expensive to make, and occupy a large amount of area on the metal housing. Accordingly, there is a need for an improved seal configuration.